The headstone of Kimberly Walker, 28, was made in the likeness of her favorite cartoon character and erected at Spring Grove Cemetery on Oct. 10, almost eight months after she was found slain in a Colorado hotel room.

Despite getting the cemetery's prior approval of the headstone's design — a smiling SpongeBob in an Army uniform, with Walker's name and rank — her family said Monday that cemetery staff called them the day after it was installed to say it would have to come down.

The 7-foot headstone, along with a near-exact duplicate erected for Walker's living twin sister, have been removed and will not be allowed back up, cemetery President Gary Freytag said Monday.

"We've decided that they aren't appropriate for our historic cemetery and they can't be displayed here," Freytag said, adding that the employee who approved the headstones made an inexplicable error in judgment, given the cemetery's traditional, stately appearance.

He acknowledged that the cemetery is at fault and that staff members would be meeting with Walker's family on Tuesday to try to find a solution, which could include a more traditional gravestone bearing small likeness of the character.

Freytag also said Spring Grove is prepared to reimburse the family for each headstone, which cost a combined $26,000, and pay for new ones.

"I feel terrible that it got to this point but I'm hoping we can come out at the other end of the tunnel with a solution," he said.

Walker was an Army corporal assigned to the 2nd General Support Aviation Battalion and served two yearlong tours Iraq in 2006 and 2010 as a petroleum supply specialist, her family said.

Walker was found dead in a hotel room in Colorado Springs on Valentine's Day this year, strangled and beaten to death. Her boyfriend, an Army sergeant stationed nearby, was arrested and charged with her killing.

Walker's twin sister, Kara Walker, said the family is beyond distraught. A lot of thought went into the gravestones, which she said were chosen because her sister loved SpongeBob, even outfitting her entire bedroom with the cartoon character's decorations.

"It is frustrating that you entrust a cemetery to have your best interest at heart and accommodate you and your family at a hard time ... and because they don't like it they're going to take it down," said Kara Walker, 29, an information technician for the U.S. Navy stationed in Naples, Italy.

"My sister served our country and most people try to accommodate veterans and try to take care of them," she said. "For them not to accommodate and respect what my sister sacrificed, not only for my family, but for everyone else in this country, really bothers me."

She said the only way the cemetery can make it up to the family, which she said pre-paid for six plots for $29,000, is to put the headstones back.

"They already brought enough grief and pain to the family," she said. "We want what we paid for and what I know my sister would have wanted."